Owners and operators of transportation equipment, manufacturing equipment and motor vehicles have tried for some time to develop an inexpensive, reliable, non-confining and non-hazardous alarm apparatus which may be worn by operators of this equipment to signal when the operator has undergone an unacceptable or dangerous motion or position. Preferably such an alarm apparatus could signal when the operator has fallen asleep. Some prior art designs have been developed for this purpose. However, these designs have proven to be cumersome and expensive, as well as provide a safety hazard in case of an accident or an unusual movement on the part of the operator. Moreover, all of these devices are capable of detecting only one type of movement by the operator.
Examples of prior art to this invention are taught by the following United States Patents: U.S. Pat. No. 2,066,092 to Brown; U.S. Pat. No. 2,711,528 to Glossbrenner; U.S. Pat. No. 2,738,496 to Armstrong; U.S. Pat. No. 2,747,038 to Perkovich; U.S. Pat. No. 2,842,628 to James; U.S. Pat. No. 2,916,572 to Ulanit; U.S. Pat. No. 3,054,868 to Phillians; U.S. Pat. No. 3,076,186 to Greene; and U.S. Pat. No. 3,964,045 to Conley.
This prior art teaches rigid structures for supporting classical switch configurations which hold one pole of a switch stationary while permitting movement of the other toward it. Switch movement may be activated by means of a plunger or other rigid apparatus. As an alternative to this first type rigid structure, the prior art teaches a tilt switch situated within a rigid case which is mounted upon the operator's head. This rigid structure, like the rigid switch structure discussed previously, provides a hazard to the operator in an accident situation. As an alternative to the above, a switch trigger mechanism including the lashing of the operator's hand to a fixed position on the vehicle to trip a signal switch has been taught. This latter apparatus obviously limits the movement of the operator's hand. Regardless of the type of structure that has been taught in the prior art, no structure teaches the monitoring of more than one type of motion or position.
What is desired, therefore, is an alarm apparatus which is capable of monitoring more than one type of movement or one position and which does not provide a hazard in an accident situation.
An object of this invention is to provide an operator movement alarm which is small, light-weight and inexpensive as well as does not present a potential accident hazard to the operator.
Another object of this invention is to provide such an alarm apparatus which is capable of signaling when the operator has assumed a specific position or is undergoing a specific motion of his body, such apparatus being capable of signaling more than one such specific position or motion.
Another object of this invention is to provide such an alarm apparatus which is positionable at different locations on the operator's body and which can alarm movement and position of one part of the body with respect to another part of the body, or of one part of the body with respect to an externally fixed object.
A further object of this invention is to provide such an alarm apparatus which will maintain the alarm signal for a fixed period of time regardless of any corrective motion by the operator.